堆石坝混凝土面板的温度场及应力场仿真研究

Simulation of temperature and stress fields in concrete face slabs of rockfill dams

基于温度—应力试验结果得到了面板混凝土的早期自收缩变形、热膨胀系数以及徐变变形。将这些参数作为面板堆石坝施工期温度场与应力场有限元仿真输入参数,研究表面保温措施对混凝土面板早期温度场与应力场的影响。仿真结果表明:表面保温措施对于混凝土面板温度场与应力场有较大影响,在合理的保温措施下,能够有效降低混凝土面板的表面与内部的温差以及混凝土面板的最大拉应力,使混凝土面板堆石坝施工期混凝土面板产生的拉应力低于抗拉强度,防止出现宏观裂缝,提高其结构安全性。

Based on the temperature and stress test results,the autogenous shrinkage deformation,thermal expansion coefficient and creep deformation of face slab concrete at early ages are obtained.These parameters are used as the input parameters of finite element simulation of temperature and stress fields in concrete face rockfill dams during construction to study the influence of surface thermal insulation measures on the early temperature and stress fields in the concrete face slab.The simulation results show that the surface thermal insulation measures have a great impact on the temperature and stress fields in the concrete face slab.Reasonable thermal insulation measures can effectively reduce the concrete temperature difference between the surface and interior of the face slab and the maximum tensile stress in concrete so that the tensile stress in the concrete face slab during construction is lower than the tensile strength.The macro cracks are prevented and the safety of the structure is improved.